FROM THIS EPISODE

At least three are dead and 170 wounded in what President Obama calls an act of "terrorism." We update yesterday's bombings at the Boston Marathon, including the impact on a historic American city. Also, the Senate "Gang of 8" hammer out a bipartisan immigration bill. On Reporter's Notebook, a bipartisan investigative task force is unanimous: the US committed "torture" with "no justification" after September 11. We talk with a retired general who served on the task force.

Banner image: Runners continue to run towards the finish line of the Boston Marathon as an explosion erupts near the finish line of the race on April 15, 2013. Photo by Dan Lampariello/Reuters

The bipartisan "Gang of 8" Senators working on immigration reform cancelled today's press conference because of yesterday's bombing. But details are emerging anyway. Under the measure, immigrants deported for non-criminal reasons before the end of 2011 would be allowed to return. That's according to Fawn Johnson with the National Journal.

Speaking of the two bombs that killed three and wounded dozens at yesterday's Boston Marathon, President Obama today announced, "Given what we now know about what took place, the FBI is investigating it as an act of terrorism." The crime scene is 12 blocks long in the heart of a city still in a state of shock. There have been no arrests and no one has claimed responsibility. Praising "exhausted runners who kept running to the nearest hospital to give blood, and those who stayed to tend to the wounded," and medical staffs and students at several local hospitals, he called on all Americans to be on the alert. We talk to Bostonians and update the investigation. What can be learned from the history of terrorism in the United States?

Former Republican Congressman Asa Hutchinson headed the DEA and was Undersecretary of Homeland Security during the Bush Administration. Because he knows so many players, he says he "took convincing." But he has "no doubts" that the President and his top advisors authorized torture in Afghanistan, Iraq, Guantanamo Bay and secret CIA "black sites" and other places. He's the co-chair of the Constitution Project's Task Force on Detainee Treatment, which includes 11 former elected officials, judges and high-ranking military officers. The nonpartisan, independent task force issued a massive report today after two years of investigation, concluding unanimously that the "unjustified" use of torture "damaged the standing of our nation, reduced our capacity to convey moral censure when necessary, and potentially increased the danger to US military personnel taken captive." One Task Force member is retired Army Brigadier General and former Republican legislator in the state of Utah, David Irvine.

Guests:David Irvine, attorney and former Republican legislator in Utah